﻿// Copyright 2004-2011 Castle Project - http://www.castleproject.org/
// 
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// 
//     http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#region 导入名称空间

using System;
using System.Reflection;

#endregion

namespace LightWork.DynamicProxy.Generators
{
    [Serializable]
    public class CacheKey
    {
        private readonly Type[] interfaces;
        private readonly ProxyGenerationOptions options;
        private readonly MemberInfo target;
        private readonly Type type;

        /// <summary>
        /// Initializes a new instance of the <see cref="CacheKey" /> class.
        /// </summary>
        /// <param name="target">Target element. This is either target type or target method for invocation types.</param>
        /// <param name="type">The type of the proxy. This is base type for invocation types.</param>
        /// <param name="interfaces">The interfaces.</param>
        /// <param name="options">The options.</param>
        public CacheKey(MemberInfo target, Type type, Type[] interfaces, ProxyGenerationOptions options)
        {
            this.target = target;
            this.type = type;
            this.interfaces = interfaces ?? Type.EmptyTypes;
            this.options = options;
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="CacheKey" /> class.
        /// </summary>
        /// <param name="target">Type of the target.</param>
        /// <param name="interfaces">The interfaces.</param>
        /// <param name="options">The options.</param>
        public CacheKey(Type target, Type[] interfaces, ProxyGenerationOptions options)
            : this(target, null, interfaces, options)
        {
        }

        public override int GetHashCode()
        {
            var result = target.GetHashCode();
            foreach (var inter in interfaces)
                result += 29 + inter.GetHashCode();
            if (options != null)
                result = 29 * result + options.GetHashCode();
            if (type != null)
                result = 29 * result + type.GetHashCode();
            return result;
        }

        public override bool Equals(object obj)
        {
            if (this == obj)
                return true;

            var cacheKey = obj as CacheKey;
            if (cacheKey == null)
                return false;

            if (!Equals(type, cacheKey.type))
                return false;
            if (!Equals(target, cacheKey.target))
                return false;
            if (interfaces.Length != cacheKey.interfaces.Length)
                return false;
            for (var i = 0; i < interfaces.Length; i++)
                if (!Equals(interfaces[i], cacheKey.interfaces[i]))
                    return false;
            if (!Equals(options, cacheKey.options))
                return false;
            return true;
        }
    }
}